重复频率泵浦钕玻璃放大器的热性能分析

重复频率激光放大器在重频工作条件下,激光增益介质的温度升高会影响其放大能力,其内部的温度梯度会影响激光光束的光学质量,甚至会发生激光增益介质的热破坏。对国产抗热冲击钕玻璃棒工作在一定频率下的温度分布和波前畸变进行了数值分析,讨论了国产抗热冲击型钕玻璃棒在重频下的工作性能并进行了实验验证。理论和实验结果表明:在1800J的氙灯泵浦能量条件下,Φ16mm×216 mm的钕玻璃棒(掺杂0.5%)在0.1 Hz工作条件下,钕玻璃棒在3 min左右就可达到热平衡,其波前畸变量为0.5λ;在400 mJ(5 ns)的注入能量条件下,其输出能量为1.2 J。

Thermal property analysis for repetition rate pumped Nd:glass amplifier

The amplification ability of laser operated in high repetition will be influenced by temperature increasing in laser material.The internal temperature gradient will affect laser qualitity and even damage the laser material.The temperature distribution and wavefront of home made thermal resistance Nd:glass rod with repetition rate operation were numerically simulated and testified in experiment.Theoretical and experimental results show that the Nd:glass rod(Φ16 mm×216 mm,0.5% Nd concentration) can reach thermal balance in 3 minutes and the laser wavefront distortion is 0.5λ when pumped by 1 800 J flash pumping with 0.1 Hz repetion rate.The ouput is 1.2 J while the input is 400 mJ(5 ns).